The present invention relates to a controlling circuit for a motorcar front window wiper accommodating apparatus and more particularly, in a concealed type wherein a wiper is accommodated within an opening portion provided between the front window lower edge and the bonnet rear-end edge, the opening portion is opened and closed by a cowl cover, to a controlling circuit for interlockingly controlling the operation between the cowl cover and the wiper.
Conventionally, in this concealed type of wiper accommodating apparatus, there are a straight-line moving type shown in FIG. 18(A), a rotary moving type shown in FIG. 18(B), and a nonlinear moving type shown in FIG. 18(C) as cowl-cover moving systems for opening and closing the wiper accommodating portion, with reference character F showing a bonnet and reference character C showing a cowl cover in each drawing. The rotary moving type is adapted to slide after the rotation during the opening operation under simple construction, with the visibility being interfered with during the opening operation, the larger space is required for the movement, and the wider space is not provided in the motorcar width direction. On the other hand, the straightline moving type vertically slides and then longitudinally slides, so that the range of vision is not interfered with and wider space is provided in the vehicle-width direction, with the gap with respect to the glass being larger, the movement not being quick.
As both the rotary moving type and the straightline moving type are of two-stage movement as described hereinabove, the opening and closing speed is slow with the movement not being smooth, thus causing the delayed feeling in the wiper actuation. Also, the moving system requires a link and a cam for changing the direction so as to complicate the construction.
In the conventional wiper accommodating apparatus of a concealed type, the opening and closing operations of the cowl cover are often effected separately from the wiper operation. The cowl cover is once opened fully by the cowl switch and the wiper is actuated by the wiper switch, provided separately. This is because the wiper wiping portion to be lifted had a possibility of interfering with the cowl cover before the cowl cover reaches the fullyopened position, thus causing delay feeling in the wiper actuation. Especially, when the mud is adhered onto the front window by mud splashes during the running operation of the vehicle to deteriorate the range of the visibility, the mud is required to be wiped through the operation of the wiper as soon as possible. However, if the wiper is actuated after the cowl cover has reached to a fully opened position as described hereinabove, the quick wiper operation can not be effected. When it takes a long time to effect the wiper operation because of the slower opening and closing speed of the cowl cover, a problem occurs in terms of safety.
The opening and closing operations of the conventional cowl cover is often adapted to be moved at a constant speed to stop the input by a position signal of a fully opened position or a fully closed position to come to a stop. In this case, the problem is that the inertia of the power source has influences upon the stop position to deteriorate the stop accuracy.